Pneumatic rubber tires are conventionally prepared with a rubber tread which can be a blend of various rubbers, typically reinforced with carbon black. In one aspect, truck tires and other relatively large tires are normally expected to be capable of supporting and carrying relatively large vehicular loads that generate a greater internal temperature than comparable passenger tires.
Truck tire treads are typically of a cap/base construction, with a tread cap designed to be ground-contacting with a lug/groove ground-contacting configuration and a tread base underlying and supporting the tread cap and positioned between the tread cap and the tire casing or carcass. Generally, the tread cap and tread base are a co-extruded component of the tire. The tread base is not intended to normally be ground-contacting and, thus, not normally intended to have the same measure of tread properties as, for example, the tread cap properties of traction and treadwear resistance.
For a typical bias ply truck tire tread cap, the tread base is relatively thick compared to the thickness of the tread cap, often 50 percent of the thickness of the tread cap instead of the relatively thin tread base of 25 percent for a passenger tire. This is in contrast to radial ply tires, such as passenger tires and light truck tires, which often have a tread of a cap/base construction where the tread base is often relatively thin (i.e., less than 25 percent of the thickness of the associated tread cap).
For such relatively heavy duty tires, heat buildup is normally undesirable, but typically unavoidable during operation of the tire under load. Thus, it remains desirable to provide a replacement tire tread for use with tires on trucks, including racing trucks, which will allow a serviceable carcass and belt reinforcement structure to be reused once the effective life of the tread has been exhausted. More specifically, racing applications generate higher temperature and heat conditions tending to prematurely wear and age the tread and thereby shorten the effective life of the tread, but typically not the carcass and belt reinforcement structure. Extending the effective life of the costly carcass and belt reinforcement structure is considered herein to be important because the above stated desire to retread the carcass and belt reinforcement structure after the tire tread becomes worn.
Further, tires generally have a tread that is well suited for a specific vehicle application. Certain tread and reinforcement packages specifically designed for truck racing are well known. The considerations relevant to a tire for such an application are, among others, tread configuration, reinforcement package disposition, and material composition. However, as would be expected, shortcomings of conventional truck racing tires remain, including excessive wear and extremely short tread life. It would be desirable to reuse the carcass and belt reinforcement structure by replacing a worn tread of a truck racing tire with a retread element.